cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-4 of 4 results.

A038677 Cubes ending in a (different) positive cube.

Original entry on oeis.org

1331, 1728, 9261, 10648, 29791, 32768, 68921, 74088, 91125, 132651, 140608, 157464, 226981, 238328, 357911, 373248, 531441, 551368, 614125, 753571, 778688, 1030301, 1061208, 1092727, 1124864, 1331000, 1367631, 1404928, 1728000, 1771561, 1815848
Offset: 1

Views

Author

N. J. A. Sloane

Keywords

Examples

			45^3 = 91125 ends with 125 = 5^3.

Links

Crossrefs

Cf. A000578 (cubes), A038678 (similar, with squares).
Cf. A145517 (the same without the "positive" restriction).

Programs

  • Mathematica
    ds[n_] := DeleteCases[NestWhileList[FromDigits[Rest[IntegerDigits[#]]] &, n, # > 9 &], 0]; Select[Range[3, 122]^3, Or @@ IntegerQ /@ (Rest[ds[#]]^(1/3)) &] (* Jayanta Basu, Jul 10 2013 *)

A065807 Squares with a smaller square as final digits.

Original entry on oeis.org

49, 64, 81, 100, 121, 144, 169, 225, 289, 324, 361, 400, 441, 484, 529, 625, 729, 784, 841, 900, 961, 1024, 1089, 1225, 1369, 1444, 1521, 1600, 1681, 1764, 1849, 1936, 2025, 2116, 2209, 2304, 2401, 2500, 2601, 2704, 2809, 2916, 3025, 3136, 3249, 3364
Offset: 1

Views

Author

Klaus Brockhaus, Nov 22 2001

Keywords

Links

Crossrefs

A065808 gives the corresponding square roots.
Cf. A038678.
Cf. A065689, A050634, A050636, A050638, A065776, A061839, A065782, A065785, A065788, A065791.

Programs

  • Mathematica
    ds[n_] := NestWhileList[FromDigits[Rest[IntegerDigits[#]]] &, n, # > 9 &]; Select[Range[4, 58]^2, Or @@ IntegerQ /@ Sqrt[Rest[ds[#]]] &] (* Jayanta Basu, Jul 10 2013 *)
  • PARI
    a065807(m) = local(a, b, d, j, k, n); for(k=1, m, a=length(Str(n))-1; b=1; j=1; n=k^2; while(b, d=divrem(n, 10^j); if(d[1]>0&&issquare(d[2]), b=0; print1(n, ", "), if(j
  • PARI
    isokend(n) = my(p=10); for(k=1, #Str(n)-1, if (issquare(n % p), return (1)); p*=10);
isok(n) = issquare(n) && isokend(n); \\ Michel Marcus, Mar 17 2020

Extensions

Changed offset from 0 to 1 by Vincenzo Librandi, Sep 24 2013

A145464 Cubes ending in a square.

Original entry on oeis.org

0, 1, 64, 125, 216, 729, 1000, 1331, 2744, 4096, 6859, 8000, 9261, 13824, 15625, 17576, 24389, 27000, 29791, 39304, 46656, 59319, 64000, 68921, 85184, 91125, 97336, 117649, 125000, 132651, 157464, 175616, 205379, 216000, 226981, 262144, 274625, 328509, 343000
Offset: 1

Views

Author

Zak Seidov, Oct 11 2008

Keywords

Comments

Cube and ending square may be equal.

Links

Crossrefs

Cf. A038678 squares ending in a (different) square.

Programs

  • Maple
    q:= n-> (s-> ormap(x-> issqr(parse(x)),
        [s[i..-1]$i=1..length(s)]))(""||n):
select(q, [i^3$i=0..120])[];  # Alois P. Heinz, Mar 16 2020
  • Mathematica
    eisQ[n_]:=AnyTrue[NestWhileList[FromDigits[Rest[IntegerDigits[ #]]]&,n,#> 9&],IntegerQ[ Sqrt[ #]]&]; Select[Range[0,70]^3,eisQ] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Oct 04 2020 *)

A145517 Cubes ending in a (different) cube.

Original entry on oeis.org

0, 1000, 1331, 1728, 8000, 9261, 10648, 27000, 29791, 32768, 64000, 68921, 74088, 91125, 125000, 132651, 140608, 157464, 216000, 226981, 238328, 343000, 357911, 373248, 512000, 531441, 551368, 614125, 729000, 753571, 778688, 1000000
Offset: 1

Views

Author

Zak Seidov, Oct 12 2008

Keywords

Crossrefs

Cf. A038678 squares ending in a (different) square, A145464 cubes ending in a square.
Cf. A038677 (for positive cubes).
Showing 1-4 of 4 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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